(1) Field of the Invention
The invention relates to automotive repair and maintenance methods and tools generally and more specifically to a torsion bar removal method and tool.
(2) Description of the Prior Art
In the prior art, the removal of a torsion bar from the rear suspension structure of a rear-engine Volkswagon automobile has been a laborious and time consuming endeavor. This is because, at rest, the torsion bar is "loaded" to produce a reaction torque forcing a cantilever arm secured to the outward end of the torsion bar into rotational engagement with a structurally integral stop adjacent the arm's cantileveled end. Normally, this cantilevered end holds the bearing which supports a wheel spindle. The axle in turn engages an axle from the transmission/differential case through universal joints so that springing action is provided responsive to vehicle load conditions and the vertical component of road shock (from bumps, chuck holes, etc.).
The removal of a torsion bar in an arrangement of the aforementioned character previously has involved apparatus working with respect to the ground or with prying means for lifting the end of the cantilevered arm from the stop. The subsequent partial removal of the spline engagement of the arm, at the outward torsion bar extremity is then difficult and must be accomplished while the pry or ground based jacking force is maintained. More than one person is required for such a procedure.
Apparatus is known for effecting the removal of various automotive component parts, such as king pins, bushings, bearings and the like. For example, U.S. Pat. No. 2,789,342 entitled "Spring Tool" discloses apparatus to lift an end of a loaded coil compression spring (in an automobile) from its bearing plate to facilitate the installation of shims to level the vehicle in its quiescent condition. A hydraulic jack forms a part of the apparatus, which will be seen to be quite different in construction and purpose vis-a-vis the present invention.
In the automotive environment, the apparatus of U.S. Pat. No. 3,217,394 provides a hydraulic portable device for in situ installation or removal of press-fitted bushings or the like. The in situ removal and reset of bushings in the automotive environment is also the subject of U.S. Pat. No. 2,859,456. In that disclosure a screw operated device is provided for in situ removal or reset of the same type of bushing.
Still another bearing/bushing removal device is shown in U.S. Pat. No. 3,103,064. However, that device differs from the aforementioned devices in that an axle assembly or the like must be removed from the vehicle and mounted in the stand according to that disclosure.
In U.S. Pat. No. 1,899,351, a closed "A" frame tool includes an internal hydraulic jack particularly designed for removal of so-called king pins from the steering and support front wheel structure of an automobile. The concept of gripping the structural part, in which the king pin resides, from both ends of the king pin prevents the applied hydraulic removal force from being applied to other parts of the automobile mechanisms, thereby avoiding damage thereto.
None of the aforementioned prior art devices is adapted to the particular use intended for the present invention and none anticipates the problem giving rise to the invention.
The manner in which the invention fills the particular need for which it was developed will be evident as this description proceeds.